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29 April 2013

How to Lock/Unlock Bootloader for Samsung Galaxy S3 SCH-I535

This guide is for show you how to unlock and lock VZW (Verizon) Samsung SCH-I535 galaxy S3 bootloader.
Verizon model of the galaxy S3 is protected from flashing modified files so that flashing by Odin always fails, and if you want to flash modified files, you need to unlock bootloader first.

Unlocking bootloader instructions :
Backup your data first

1- Extract and Open "Odin3" as administrator (Link below)
2- Click on "PDA" button and browse to "VRALEC.bootchain.tar.md5" file (Link below) 
3- Disconnect any device connected to USB ports on your computer and disable your antivirus software
4- Shut down your device then Put it into Download Mode (Volume Down + Home + Power)
5- Volume up to continue
6- Connect the device to your computer by USB cable and wait until you get a sign in Odin (ID:COM section) and "Added" in message
7- Make sure re-partition is NOT SELECTED [important]
8- Click Start and wait a few seconds.
Done !

Locking bootloader instructions :

Its exactly the same of unlocking process but with different flashing file.
#2- Click on "PDA" button and browse to :
"VRBLK3_bootchain.tar.md5" file [if your device on jelly bean 4.1.1] or
"VRBMB1_bootchain.tar.md5" file [if your device on jelly bean 4.1.2] (Links below) 

Notes :
~ Its recommended to lock bootloader after you finish rooting or flashing custom recovery.
~ Download and Install Kies or Samsung mobile driver, if you didn't get a sign in ID:COM or "Added" in message box
~ I am not responsible if something bad happened to your device (use this AT YOUR OWN RISK)
~ This Tutorial for unlocking/locking bootloader NOT UNLOCKING NETWORK CARRIER

Downloads :
Odin3_v3.04 HERE, v3.07 HERE, v3.09 HERE
"VRALEC.bootchain.tar.md5" Unlock bootloader LINK
"VRBLK3_bootchain.tar.md5" Lock bootloader LINK (jelly bean 4.1.1)
"VRBMB1_bootchain.tar.md5" Lock bootloader LINK (jelly bean 4.1.2)
Latest Samsung Mobile Driver HERE
Latest Samsung Kies HERE


  1. So, I do this, then the instructions for the rooting process?

  2. So, after doing this process, and then the rooting process on the other page, my phone will be unlocked to use programs that will only work on rooted phones and things like that? What other things can I do by having an unlocked and rooted phone?

    1. You can modify system files, install custom recovery, custom Rom, Apps which need root permission, remove bloat ware and many features

  3. I followed the root process but I am still getting the NON VERZON SIM meesage and can't use the data with AT&T. Did I miss anything

    1. this unlocks the verizon bootloader (which prevents u from downloading certain apps and doesnt allow u to delete certain ones, etc.), This has nothing to do with unlocking the sim card, thats a different kind of unlock. u can call verizon global services and they can give u an unlock code as long as u agree to only use foreign sims when traveling abroad. this worked for me when i go overseas, but i never tried any local sim but im sure verizon locks that out.

  4. wtf!! i did it and the phone doesn´t turn on anymore, doesn´t even turns on te led when i connected... what can i do??

    1. If your device can boot into download mode, flash official FW
      If it can't, use the warranty

  5. how to root a galaxz s3 mini clone?

  6. Im trying to relock my bootloader and i already flashed the file but it just boots back up but its still unlocked ? What the heck? Please respond as ssoon as possible!

  7. Same problem here. locked bootloader flashes successfully, and appears to be locked on first boot, but subsequent boots are unlocked again. There is some black magic going on here... Any ideas?

  8. asshole my wifi isnt working now! Is anyone else having this problem? :/